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Related papers: Silicate Evolution in Brown Dwarf Disks

200 papers

We present Spitzer images of the Taurus Complex (TC) and take advantage of the sensitivity and spatial resolution of the observations to characterize the diffuse IR emission across the cloud. This work highlights evidence of dust evolution…

This paper presents the results of a search for brown dwarfs in the Upper Scorpius Association using data from the UKIRT Infrared Deep Sky Survey (UKIDSS) Galactic Cluster Survey. Candidate young brown dwarfs were first chosen by their…

Solar and Stellar Astrophysics · Physics 2015-05-30 P. Dawson , A. Scholz , T. P. Ray

An accurate knowledge of the mineralogy (chemical composition and crystal structure) of the silicate dust in the interstellar medium (ISM) is crucial for understanding its origin in evolved stars, the physical and chemical processing in the…

Astrophysics · Physics 2009-11-13 M. P. Li , G. Zhao , Aigen Li

Absorption lines in the spectra of distant quasars whose sightlines pass through foreground galaxies provide a valuable tool to probe the dust and gas compositions of the interstellar medium (ISM) in galaxies. The first evidence of silicate…

Astrophysics of Galaxies · Physics 2014-05-05 Monique C. Aller , Varsha P. Kulkarni , Donald G. York , Daniel E. Welty , Giovanni Vladilo , Debopam Som

We present the first comprehensive, comparative Spitzer/IRS study of the dust and gas properties of disks around young sun-like stars (K1-M5) and cool stars/brown dwarfs (M5-M9). The comparison of these two large samples of over 60 sources…

Astrophysics · Physics 2011-02-11 I. Pascucci , D. Apai , K. Luhman , Th. Henning , J. Bouwman , M. Meyer , F. Lahuis , A. Natta

We present Spitzer 3.6--24 micron photometry and spectroscopy for stars in the 1--3 Myr-old Coronet Cluster, expanding upon the survey of Sicilia-Aguilar et al. (2008). Using sophisticated radiative transfer models, we analyze these new…

Solar and Stellar Astrophysics · Physics 2015-05-27 Thayne Currie , Aurora Sicilia-Aguilar

Context. Although many studies have been performed so far, there are still dozens of low-mass stars and brown dwarfs in the young sigma Orionis open cluster without detailed spectroscopic characterisation. Aims. We look for unknown strong…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. A. Caballero , A. Cabrera-Lavers , D. Garcia-Alvarez , S. Pascual

Protoplanetary discs in the Upper Scorpius star-forming region are excellent laboratories to investigate late stages of planet formation. In this work, we analyse the morphology of the dust continuum emission of 121 discs from an ALMA Band…

Resolved submillimeter imaging of transitional disks is increasingly revealing the complexity of disk structure. Here we present the first high-resolution submillimeter image of a recently identified transitional disk around IRAS 04125+2902…

Earth and Planetary Astrophysics · Physics 2015-07-15 C. Espaillat , S. Andrews , D. Powell , D. Feldman , C. Qi , D. Wilner , P. D'Alessio

Studies of disks around young brown dwarfs are of paramount importance to our understanding of the origin, diversity and early evolution of sub-stellar objects. Here we present first results from a systematic search for disk emission in a…

Astrophysics · Physics 2007-05-23 Ray Jayawardhana , David R. Ardila , Beate Stelzer

Most brown dwarfs have atmospheres with temperatures cold enough to form clouds. A variety of materials likely condense, including refractory metal oxides and silicates; the precise compositions and crystal structures of predicted cloud…

Solar and Stellar Astrophysics · Physics 2021-11-03 Jessica L. Luna , Caroline V. Morley

We present new Atacama Large Millimeter/submillimeter Array (ALMA) observations for three protoplanetary disks in Taurus at 2.9\,mm and comparisons with previous 1.3\,mm data both at an angular resolution of $\sim0.''1$ (15\,au for the…

We perform coagulation & fragmentation simulations to understand grain growth in T Tauri & brown dwarf discs. We present a physically-motivated approach using a probability distribution function for the collision velocities and separating…

Earth and Planetary Astrophysics · Physics 2013-08-26 Farzana Meru , Marina Galvagni , Christoph Olczak , Pascale Garaud

We present 7-mm continuum observations of 14 low-mass pre-main-sequence stars in the Taurus-Auriga star-forming region obtained with the Very Large Array with ~1.5" resolution and ~0.3 mJy rms sensitivity. For 10 objects, the circumstellar…

Astrophysics · Physics 2009-11-11 J. Rodmann , Th. Henning , C. J. Chandler , L. G. Mundy , D. J. Wilner

While beta Pic is known to host silicates in ring-like structures, whether the properties of these silicate dust vary with stellocentric distance remains an open question. We re-analyze the beta Pictoris debris disk spectrum from the…

In order to investigate possible connections between dust processing and disk properties, 8--13 um spectra of 34 young stars, with a range of circumstellar environments and spectral types A to M, were obtained using the Long Wavelength…

Astrophysics · Physics 2009-11-10 J. E. Kessler-Silacci , L. A. Hillenbrand , G. A. Blake , M. R. Meyer

We investigate the IR spectral features of a sample of D-type symbiotic stars. Analyzing unexploited ISO-SWS data, deriving the basic observational parameters of dust bands and comparing them with respect to those observed in other…

Astrophysics · Physics 2008-11-26 R. Angeloni , M. Contini , S. Ciroi , P. Rafanelli

We present a model of the circumstellar environment of the so-called ``Butterfly Star'' in Taurus (IRAS 04302+2247). The appearance of this young stellar object is dominated by a large circumstellar disk seen edge-on and the light…

Astrophysics · Physics 2008-11-26 Sebastian Wolf , Deborah L. Padgett , Karl R. Stapelfeldt

We investigate the composition and shape distribution of silicate dust grains in the interstellar medium. The effect of the amount of magnesium in the silicate lattice is studied. We fit the spectral shape of the interstellar 10 mu…

We present new results from a significant extension of our previous high angular resolution (0.3" = 40 AU) Submillimeter Array survey of the 880 um continuum emission from dusty circumstellar disks in the ~1 Myr-old Ophiuchus star-forming…

Solar and Stellar Astrophysics · Physics 2015-05-19 Sean M. Andrews , D. J. Wilner , A. M. Hughes , Chunhua Qi , C. P. Dullemond